Recessed “downlight” luminaires, sometimes referred to as “pot lights” or “can lights,” are widely used in commercial and residential lighting applications. The luminaries typically consist of an outer enclosure or housing, a light source inside the housing, and a reflector to help direct light out of the luminaire. The reflectors are available in a multitude of shapes and designs intended for various applications, and can typically have a specular reflection surface such as polished metal, a diffuse reflection surface such as a white painted surface, or a diffuse/specular reflection surface such as brushed or coated aluminum.
When light sources, such as compact fluorescent lamps or LEDs (light emitting diodes) with broad distribution patterns are used in downlights, luminaire efficiency tends to be relatively low, with an average efficiency typically less than 60%, which may be due to light losses within the reflector. The possible range of sizes and shapes of reflector design are typically limited by the geometry of the housing, lamp placement, and the luminaire's light distribution considerations. A large percentage of light emitted from the light source may become “trapped” within the reflector and may be significantly attenuated by multiple reflections before exiting the luminaire.